I currently have a 4870x2, and Crossfire is really bugging me. I want to upgrade to a single GPU solution.

I only game at 2560x1600, and I would like to know what the best choice is. The 480 is more powerful, a $100 more expensive. Is it worth jumping from 4870x2 to the 480? Or should I get on the less powerful 5870?

I currently have a 4870x2, and Crossfire is really bugging me. I want to upgrade to a single GPU solution.

I only game at 2560x1600, and I would like to know what the best choice is. The 480 is more powerful, a $100 more expensive. Is it worth jumping from 4870x2 to the 480? Or should I get on the less powerful 5870?

My cpu is a q9550 at 3.7. How much big of a bottleneck would this be?

I'd say the GTX480. Your 4870X2 has pretty similar power/heat/noise, so you're used to that. The only 5870s that are $100 cheaper than 480s have 50% less RAM, which can come into play at your 25X16 resolution.